Allen's Damselfish

Allen's Damselfish ([Pomacentrus alleni]) is a semi-aggressive species that is reef-safe with caution, admired for its vibrant electric-blue coloration, compact size, hardy nature, and striking neon-like sheen.

Males typically display more intense coloration and become territorial, especially when guarding a nest or territory, while females/juveniles exhibit slightly duller blue tones and less aggressive behavior.

They reach about 2–3 inches and should be housed in aquariums of at least 30 gallons. Provide a sandbed, plenty of live rock with hiding spots, and open swimming space, stable water parameters (salinity ~1.020-1.025, temp ~72-79°F, pH ~8.1-8.4), and a secure lid since many species are prone to jumping.

Diet should consist of mysis shrimp, brine shrimp, copepods, high-quality pellets, and algae. With proper care, this fish makes a standout addition to the aquarium, adding dazzling color and lively activity to a reef environment.

International Aquatics Quarantine & Guarantee: All fish are checked by marine vets, given a formalin bath, and held for 14 days in copper-treated systems. We feed Selcon-soaked food with Kanaplex and Metroplex during quarantine. Unless marked, all livestock comes with our 15-Day Guarantee. You will receive a video of your fish eating before shipment. On request, we also send photos/videos after arrival at IA. Some species are import-to-order (3-10 business days). Many common species are already cleared or near the end of QT.

Several species will be import-to-order and may take anywhere from 3-10 business days to secure. Once your fish is secured, you will be notified, and the quarantine process will then begin.